Patients with poison exposure and toxicity may present with a spectrum of various clinical signs, symptoms, and problems. Most of these are very straightforward and easily anticipated, but others may be unpredictable or associated with exposure to unidentified substances that hinder the clinician from knowing what to expect. There are, however, general principles that may be employed as a framework on which approach to most poisonings may be based. These are employed when managing adverse effects from poisoning by known or unidentified substances. Less than 5% of poisonings require use of specific antidotes; thorough general supportive care is the most important approach in caring for most poisoned patients.1
The initial principles of management of poisoned patients generally follow the protocol used for the management of urgent and emergent problems. There are some slight differences if the “airway, breathing, circulation” approach is used, with some specific amendments relevant to poison exposures and toxicity. “Airway, breathing, circulation, disability, dextrose, exposure, ECG” comprise the general “A, B, C, D, D, E, E” mantra of poison management. This may differ from other emergency department (ED) management in that “disability” and “exposure,” necessary for patients with trauma, are not essential in most poisoned patients, but can reveal some valuable diagnostic information.
Critical to proper management of poisoning is recognition that poison exposure occurred. When evaluating a poisoned patient, a good approach is to identify the reason of exposure (i.e., intentional, unintentional, misadventure), the type of substance involved (i.e., prescription, over-the-counter, herbal, illicit drug), the formulation (i.e., immediate vs. sustained release), the dose of the substance, the amount of substance involved, the route of exposure (i.e., ingestion, inhalation, intravenous, dermal), the time of exposure (hours since exposure, acute vs. chronic), any potential coingestion, and the severity of exposure.
Obtaining a medical history from the poisoned patient may be difficult, and, therefore, other people such as family members, friends, prehospital personnel, the patient's physician or therapist, or previous medical records may provide crucial information to aid in management. Thorough medical knowledge of all ailments, medical history, medication history, and other medications or substances the patient had access to often provides useful information.
After initial assessment, stabilization, and physical exam, further management may include (1) decontamination, (2) prevention of absorption, (3) administration of antidote, and (4) enhanced elimination of the toxic substance.
Examination of patients with poison exposure and toxicity is often more focused than a general physical examination, with particular attention to areas that are expected to yield useful information (Table 40-1).
Table 40-1. Common Findings in Poisoning |Favorite Table|Download (.pdf)
Table 40-1. Common Findings in Poisoning
|Clinical and/or laboratory findings in poisoning|
|Agitation||Anticholinergics,a ethanol and sedative–hypnotic withdrawal, hypoglycemia, phencyclidine, sympathomimeticsb|
|Alopecia||Alkylating agents, radiation, selenium, strontium, thallium|
|Ataxia||Benzodiazepines, carbamazepine, carbon monoxide, ethanol, hypoglycemia, lithium, mercury, phenytoin, nitrous oxide|